Device for allowing adjustment of the position of a steering member in a vehicle

ABSTRACT

The present invention relates to a device for allowing adjustment of the angular position of a steering member ( 2 ) in a vehicle. The device comprises an upper portion ( 3 ) arranged to be connected to the steering member ( 2 ), a lower portion ( 4 ), steering means arranged to connect the upper portion ( 3 ) and the lower portion ( 4 ) along at least a curved path such the steering member ( 2 ) is adjustable in a plurality of angular positions in relation the lower portion ( 4 ). The curved path has a curvature, which forms a centre of curvature ( 6 ) located between the steering member ( 2 ) and the driver ( 1 ) and in an area at or in immediate vicinity of the wrist of the driver ( 1 ).

BACKGROUND OF THE INVENTION AND PRIOR ART

[0001] The present invention relates to a device for allowing adjustmentof the position of a steering member in a vehicle according to thepreamble of claim 1.

[0002] Known devices for adjusting the position of the steering members,as steering wheels, in motor vehicles comprise usually a mechanism,which allows a position adjustment of the steering wheel at leastvertically. After a driver has performed such an adjustment of thesteering wheel, the risk exists that it blocks important instruments inthe instrument panel. In many cases, the driver has therefore to make acompromise between a comfortable driving position and a clear view ofimportant instruments in the instrument panel.

[0003] SE 457 871 shows a device in a vehicle which allows an automaticadjustment of the position of a steering wheel during operation of thevehicle. The steering wheel is attached to an upper part of the device,which is articulately provided in relation to a lower part, via a joint.The joint is located a distance behind the steering wheel in relation tothe driver. A changed angular adjustment of the steering wheel resultsin this case also in an adjustment of the position of the steering wheelvertically. Therefore, a completely variable adjustment of the steeringwheel may not be obtained by this device.

[0004] U.S. Pat. No. 4,537,089 shows a device which allows adjustment ofa steering wheel in different angular positions. The steering wheel isattached to the device at an upper portion, which is displaceablyprovided in relation to a lower portion along a curved path. Thesteering wheel is here possible to displace along the curved path, whichhas a centre of curvature located relatively far away from the steeringwheel and near the driver. Also here, a changed angular adjustment ofthe steering wheel is associated with a vertically changed adjustment ofthe steering wheel. A completely optimal adjustment adapted to theindividual driver may therefore not either be obtained by this device.

SUMMARY OF THE INVENTION

[0005] The object of the present invention Is to provide a device foradjustment of the position of a steering member in a vehicle, whichdevice allows a substantially arbitrary angular adjustment of thesteering member starting from a first adjustment of the steering memberadapted to the driver.

[0006] This object is achieved by the device of the initially mentionedkind, which is characterised by the features specified in thecharacteristic part of claim 1. An optimally adapted position of asteering member for a driver comprises a correct adjustment of thesteering member vertically and a correct adjustment of the distancebetween the driver and the steering member. After a driver has adjustedthe steering member to such a position allowing a comfortable drivingposition, the steering member may in certain cases wholly or partlyblock important instruments provided in the instrument panel. Since thesteering member is possible to set in different angles around a centreof curvature, which is located ahead of the steering member and at adistance from 1 to 10 cm from a plane extending through the grip areasof the steering member, said centre of curvature will be located at orin immediate vicinity of the wrist of the driver. Thereby, the drivermay substantially with a simple movement of the wrist, turn the steeringmember to a desired position for the driver where important instrumentsare not blocked. Since the movement of the wrist is executed by thewrist in a substantially fixed position, the driver may keep hiscomfortable posture during and after such an adjustment of the positionof the steering member.

[0007] According to a preferred embodiment of the present invention,said centre of curvature is located at a distance from 4 to 7 cm fromsaid plane extending through the grip areas of the steering member.Normally, the distance from a fulcrum of a wrist of a person to a centregrip point in the hand is about 6 cm. However, the wrist is usually heldsomewhat angled when the steering member is gripped such the distancefrom the wrist to said plane is somewhat lesser than 6 cm for anordinary person when the steering member is gripped. By providing acentre of curvature at a distance from 4 to 7 cm from said plane, thereis substantially no movements of the wrists for the most drivers duringan angular adjustment of the steering member. If the steering member isa steering wheel having an annularly extended grip surface, the centreof curvature is provided above the part of the grip surface of thesteering wheel which is the most natural to grip for the driver.

[0008] According to another preferred embodiment of the presentinvention, anyone of said lower portion and upper portion of the devicecomprises the curved path whereas the other portion comprises at least aposition member which is arranged to be displaceable along said curvedpath. The position member may be adjustable in a continuous manner alongsaid curved path such that a continuous angular adjustment of thesteering member is obtained or be adjustable in advanced determinedfixed positions along the curved path. Advantageously, a first curvedpath comprises a first upper surface and a second curved path a secondlower surface and that at least a first position member is arranged tobe displaceable along the first upper surface and at least a secondposition member is arranged to be displaceable along the second lowersurface. Since the curved paths comprise an upper surface and a lowersurface having position members which are provided in contact with therespective surfaces, a stable control may be obtained between the upperportion and the lower portion when they are angularly adjusted inrelation to each other.

[0009] According to another preferred embodiment of the presentinvention, at least anyone of said first position member and secondposition member comprises a body having a surface, which is slideablyprovided along said first surface or a said second surface.Advantageously, such a body has in the contact surface with the curvedpath a corresponding curved shape. According to an alternative, at leastanyone of said first position member and said second position member maycomprise a wheel member which is rollably provided along said firstsurface or said second surface. By the wheel member, a very low frictionbetween the wheel member and the surface of the curved path is obtainedduring such a displacement motion. Said wheel member and said surfacemay comprise co-operating gears. Thereby, a stable contact between theupper portion and the lower portion is obtained and the risk for a skewsetting of the position members along the curved path is eliminated.

[0010] According to another preferred embodiment of the presentinvention, the lower portion is attachable to a second adjusting device,which allows adjustment of the lower portion in a plurality ofpositions. By such an adjusting device, the steering member initiallymay be placed in a position adapted to the individual driver.Thereafter, the driver may turn the steering member in a desired angularposition by means of a wrist motion without changing his adjusteddriving position in the vehicle.

[0011] According to another preferred embodiment of the presentinvention, the upper portion comprises a passage through which asteering shaft, which is connected to the steering member, is arrangedto extent. In order to transmit the turned position of the steeringmember to the steerable wheels of the vehicle, said steering shaft isused, which extents down through the upper portion. Advantageously thesteering member is a steering wheel. Usually, steering wheels are usedas steering members in vehicles and they have a construction, which inmany cases blocks parts of the instrument panel.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In the following is described as an example a preferredembodiment of the invention with reference to the attached drawings, inwhich:

[0013]FIG. 1 shows schematically a device according to the presentinvention for adjusting the angular adjustment of a steering wheel,

[0014]FIG. 2 shows the device in FIG. 1 more in detail seen from theside,

[0015]FIG. 3 shows the device in FIG. 2 seen from the front,

[0016]FIG. 4 shows a lock mechanism for allowing locking of the steeringmember in a desired angular position.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE PRESENT INVENTION

[0017]FIG. 1 shows a driver 1, which is arranged to steer a vehicle by asteering member in form of a steering wheel 2. A device for allowingadjustment of the angular position of the steering wheel 2 comprises anupper portion 3, which is fixedly provided in relation to the steeringwheel 2, and a lower portion 4, which is adjustable in differentpositions vertically by a second adjusting device 5. The secondadjusting device 5 shows schematically in FIG. 1. The upper portion 3 isconnected to the lower portion 4 along two curved paths. The upperportion 3 and thereby the steering wheel 2 may be adjusted in differentangles in relation to the lower portion 4 by said curved paths. Thecurved paths have a corresponding curvature having a centre of curvature6, which is located on the opposite side of the device of the steeringwheel 2. Said centre of curvature 6 is arranged to coincide with or belocated at a too small distance as possible from a fulcrum of the wristof the driver 1. Such a centre of curvature 6 is defined by an axishaving a perpendicular extension to a plane (p), which is shown inFIG. 1. Said plane (p) has an extension, which extends through thenatural grip areas of the driver on the grip surface of the steeringwheel 2. The steering wheel 2 has a substantially annular grip surface,which extends and is pivotal around a fulcrum. Said centre of curvature6 is located above the natural grip areas of the steering wheel 2, i.e.at a distance from said plane (p). In private cars, the natural gripareas on the steering wheel are located about 60° from the highestlocated point of the steering wheel 2 and in heavy vehicles locatedsomewhat more than 90° from the highest located point of the steeringwheel 2. Since persons in normal case have a distance from the fulcrumof the wrist to a grip point in the hand of about 6 cm, it is suitableto provide said centre of curvature 6 at a distance from 4 to 7 cm fromthe natural grip areas of the steering wheel 2.

[0018]FIGS. 2 and 3 show the device in FIG. 1 more in detail. Hereby, itis evident that the upper portion 3 comprises a passage 7 through whicha steering shaft, which is connected to the steering wheel 2, isarranged to extent. Suitable attachment means are provided forattachment of the steering wheel 2 to the upper portion 3. However,these attachment means are not shown in the figures. The upper portion 3comprises a first curved path having an upper curved surface 8 whichconstitutes a part of a curved recess 9 and a second curved pathcomprising a lower surface 10 which comprises a plurality of gears 11.The upper curved surface 8 and the lower curved surface 10 have acorresponding curvature such they have a common centre of curvature 6.The upper portion 3 comprises such curved paths at each of its sidesurfaces. The lower portion 4 comprises substantially two leg-shapedportions 4 a, b, which extent upwards to the upper portion 3. Each ofthe leg-shaped portions 4 a, b comprises at an upper end a positionmember in form of a slide element 12, which is provided on a protrudingrod 13. The slide elements 12 are displaceably provided in the curvedrecesses 9 and slideably provided along the upper curved surface 8.Consequently, the lower portion 4 comprises totally two slide elements12. Each of the leg-shaped portions 4 a, 4 b, comprises at its upper endalso position members in form of two gear wheels 14. Consequently, thelower portion 4 comprises totally four gear wheels 14. The gear wheels14 is arranged to roll along the lower curved surface 10 which comprisesgears 11 of a corresponding size. By means of the position members12,14, the upper portion 3 and the lower portion 4 are guided along thecurved paths in relation to each other. Since the position members 12,13are connected to the lower portion 4 at the upper curved surface 8 aswell as at the lower curved surface 9 of the upper portion 3, a stableguiding of the upper 3 and the lower portions 4 is obtained where theyare angle adjusted in relation to each other. The curved recess 9comprises end portions, which restrict the motions of the slide elements12 along the upper curved surface 8. Thereby, these end portionsrestrict the maximum angle v, which may be obtained between the upperportion 3 and the lower portion 4.

[0019] In order to lock the upper portion 3 in relation to the lowerportion 4 in an adjusted angular position, a locking device is provided.The locking device is shown separately in FIG. 4 and it comprises alinked mechanism 15, which is loaded in an upward direction by a gasspring 16. The linked mechanism 15 extents up through the leg-shapedportions 4 a,b of the lower portion 4 between the gear wheels 14 and isended by an end portion 17, which comprises a recess having acorresponding shape as the gears 11 of the lower curved surface 10. Theend portion 17 is pressed upwards by a force produced by the gas spring16 such it receives and keeps the nearest located gear 11 in its recess.Thereby, the upper portions 3 and the lower portions 4 are lockable inrelation to each other in a substantially arbitrary adjusted angularposition.

[0020] The lower portion 4 comprises an inclined surface 18 between theleg-shaped portions 4 a,b of the lower portion 4. This surface 18 isarranged to abut to a corresponding incline surface of the secondadjusting device 5. These inclined surfaces are arranged to bedisplaceable in relation to each other such the lower portion may beadjusted vertically. The second adjusting device 5 also comprises a lockmechanism in order to allow locking of the surface 18 in relation to thecorresponding surface of the second adjusting device 5 in a plurality ofpositions. Consequently, the second adjusting device 5 allows anadjustment of the steering wheel 2 vertically in a desired position forthe driver.

[0021] Initially, when a driver has to use a vehicle, the position ofthe steering wheel 2 is adjusted when need arises by the secondadjusting device 5 such the steering wheel 2 obtains a desired verticalposition for the driver. If, for example, the steering wheel 2 in thisposition blocks important instruments in the instrument panel or if thedriver by any other reason desires to set the steering wheel 2 inanother angle, the driver grips the normally intended gripped surface ofthe steering wheel 2 with at least one hand. Thereafter, the driverdisplaces the linked mechanism 15 downwardly with, for example, theother hand by a suitable control member against the action of the gasspring 16. The end portion 17 also is displaced downwardly and itslocking of the received gear 11 is discontinued. Since the upper curvedsurfaces 8 and the lower curved surfaces 10, along which the slideelements 12 and the gear wheels 13 are displaceable, have a curvaturewhich forms a centre of curvature 6 in or in immediate vicinity of afulcrum of the wrist of the driver 1, the driver 1 may with a simplemovement of the wrist now turn the steering wheel 2 to a desired angularposition. Consequently, the driver 1 may remain his present comfortabledriving position independently of the angular position of the steeringwheel 2. After the adjustment of the steering wheel in an desiredangular position, the driver release said reglage and the gas spring 16again displaces the linked mechanism 15 and the end portion 17 upwardsto a locked position of the now nearest located gear 11.

[0022] The present invention is not in any way restricted to theabove-described embodiments in the drawings but may be modified freelywithin the scope of the claims. For example, the described lockmechanism is not necessary to use but a functional lock mechanism of asubstantially arbitrary kind may be used.

1. A device for allowing adjustment of the position of a steering memberin a vehicle, wherein the steering member comprises at least two gripareas located at a distance from each other and arranged to be grippedby the respective hands of a driver (1) in a normal position of use ofthe steering member, said grip areas having an extension substantiallyalong a plane (p) extending through said grip areas, and wherein thedevice comprises an upper portion (3) arranged to be connected to thesteering member (2), a lower portion (4) arranged to be fixedly providedin at least a first position in the vehicle, steering means arranged toconnect the upper portion (3) and lower portion (4) along at least acurved path such the steering member (2) is adjustable in at least twoangle positions in relation to the lower portion (4) and a lockingdevice arranged to lock the upper portion (3) in relation to the lowerportion (4) in the adjusted angle position, characterised in that thecurved path has a curvature, which forms a centre of curvature (6) onthat side of said plane (p) which is turned away from the upper portion(3) of the device and at a distance from 1 to 10 cm from the plane (p).2. A device according to claim 1, characterised in that said centre ofcurvature (6) which is provided at a distance from 4 to 7 cm from saidplane (p).
 3. A device according to claim 1 or 2, characterised in thatone of said upper portion (3) and said lower portion (4) of the devicecomprises the curved path whereas the other portion comprises at leastone position member (12, 14) which is arranged to be moveable along saidcurved path.
 4. A device according to claim 3, characterised in that afirst curved path comprising a first surface (8) and a second curvedpath comprising a second surface (10) and that at least a first positionmember (12) is arranged to be moveable along the first surface (8) andat least a second position member (14) is arranged to be moveable alongthe second surface (10).
 5. A device according to claim 4, characterisedin that at least anyone of said first position member (12) and secondposition member (14) comprises a body having a surface which is slidablyprovided along said first surface (8) or said second surface (10).
 6. Adevice according to claim 4 or 5, characterised in that at least anyoneof said first position member (12) and second position member (14)comprises a wheel member which is rollably provided along said firstsurface (8) or second surface (10).
 7. A device according to claim 6,characterised in that said wheel member (14) and surface (10) compriseco-operating gears.
 8. A device according to any one of the precedingclaims, characterised in that the lower portion (4) is attachable to asecond adjusting device (5) which allows positioning of the lowerportion (4) in a plurality of positions.
 9. A device according to anyone of the preceding claims, characterised in that the upper portion (3)comprises a passage (7) through which a steering shaft, which isconnected to the steering member (2), is arranged to extend.
 10. Adevice according to any one of the preceding claims, characterised inthat the steering member comprises a steering wheel (2).